It's frequent for me who is an affectionado of Asian movies to be the first reviewer of Asian movies. I hope this one serves to give some background about this movie.
This is an interesting movie, and one of the best Asian horror movies I've seen. The original novel was authored by Kagen and was available as download from mobile telephone site "Mahouno i rando" (魔法のiらんど). This site caters to high school girls, and has its unique culture designed to serve girls in this age group.
Satomi (Umika Kawashima), and Yuka (Aki Asakura) are high school friends. One day on their way home from school, they encounter a suicide of their friend Mayumi (Miki Nakagawa). In the hand of the victim was a cell phone connected to a site that offers Keitai kareshi, or mobile boyfriend. Suspecting that the mobile boyfriend had something to do with it, Yuka attempts to connect with the boyfriend Riku that Mayumi was communicating with. But she's already subscribed to another mobile boyfriend, and her phone won't accept a new one, so she uses Satomi's cell phone. Riku, Satomi's new virtual boyfriend starts communicating with Satomi. The game is based on sort of artificial intelligence, but there seems to be more behind the response it gives. There's a gauge that appears on the phone indicating the degree of affinity the two supposed lovers has. Satomi has a part time job, and at work, Eri Aikawa (Nozomi Maeda) her coworker looks into Satomi's cellphone and sees Satomi's gauge has gone down to 10%. During work, Eri transfers Satomi's virtual boy friend into her phone. Eri is successful in getting the gauge up to 100%. Then she gets a message "Die !". A ghostly shadow appears and causes Eri to die from electricution in the bathroom. Satomi discovers Eri's dead body in the bathroom. Now Satomi is convinced that mobile boyfriend has something to do with death of the girls. Satomi has a real love interest Naoto (Hideo Ishiguro) who's a senior in her school. She hears on the news that Naoto died in a fire along with group of youngsters who formed a group of rape gang. Due to shock, she is hospitalized. Police officers Igarashi (Shigemitsu Ogi) and Asanuma (Mari Hoshino) pays Satomi a visit at the hospital. They inquire about Eri's death. Satomi tells them that both who died were playing mobile boyfriend, and Eri was murdered by Riku, but the two officers don't take her seriously. Yuka tells Satomi that rumor is going around the internet that when the gauge hits 0 or 100, that person dies. She witnesses another death of a girl with her phone connected to mobile boyfriend's site. Yuka is terrified because her gauge is getting low, and asks Satomi to transfer her mobile boyfriend into hers, but Satomi is too scared to accept. Yuka attempts to get rid of her phone at the garbage dump, but she finds it returned to her mailbox. Satomi gets a call from Kumi (Sakina Kuwae) her old class mate. She wants Satomi to transfer her mobile boyfriend. Satomi is shocked to find out that Kumi's mobile boyfriend is Naoto who died in the fire. She accepts the transfer. Yuka asks Satomi to help her. She's nearly hysterical with fear, and destroys her phone. Yuka and Satomi goes to get a new phone for Yuka, but somehow the mobile boyfriend finds her new phone and contacts her. Satomi goes to the two police officers who've paid her a visit at the hospital. They transfer one of the mobile boyfriend to officer Asanuma's phone. She plays the game and commits suicide in front of officer Igarashi. Igarashi is now convinced that mobile boyfriend is killing people, and contacts Satomi to solve the case.
There's some inconsistencies in the timeline of this story (or watching the movie gives this impression). The people who have become the mobile boyfriend died in the fire after Mayumi's death, but Mayumi died playing the mobile boyfriend. Maybe the timeline is moving back and forth in the movie, but it sure isn't clear from watching it.
This is a really good movie that's not just simple horror, but has intriguing story to it. This is also the directorial debut for director Shinjyu Funabiki. She did a great job of portraying the horror mystery intelligently without excessive panic scenes. The casting is great, and has many young A list actors playing the parts. Umika Kawasaki, and Aki Asakura who've played the lead and the co-lead were great in this movie. Same goes for Hideo Ishiguro who played Satomi's love interest.
One of the best movie to come out of Japan in recent years horror or otherwise, and is recommended for viewing.